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Real-Time Measurement and Control

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NI 9853 missing CAN Recive signals

Hi,

I have encoutered a problem with NI 9853 communication. I am using cRIO 9049.

 

When I want to read data from CAN using NI X-net database I am reading most of the frames, but few of them are missing. Above that, from time to time, some values are freezing for short period of time. Does anyone know what could possibly be wrong? I attach screen of FPGA code and VI on RT that is responsible for reading this values.

 

I am reading it in this way, becouse I need to refresh all values in certain period of time. This is my try of solving this issue. Mine goal is to update all frames every 10ms on RT.

 

Do I even need a loop timer in my loop ? How exactly works CAN Read property node block? Does it wait for CAN signal or it executes last value if CAN signal haven't been recived yet? 

 

I would be grateful for any tips and help.

 

FPGA CAN Read.png

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Hi,

 

Have you checked the XNET compact RIO example? It's in the example finder. You can refer to that. Basically, FPGA code is written to send CAN frames to RT. 

You can get some ideas by looking at code.

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